.\" zip_source_read.mdoc -- read data from zip source
.\" Copyright (C) 2014-2022 Dieter Baron and Thomas Klausner
.\"
.\" This file is part of libzip, a library to manipulate ZIP archives.
.\" The authors can be contacted at <libzip@nih.at>
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.Dd September 28, 2021
.Dt ZIP_SOURCE_READ 3
.Os
.Sh NAME
.Nm zip_source_read
.Nd read data from zip source
.Sh LIBRARY
libzip (-lzip)
.Sh SYNOPSIS
.In zip.h
.Ft zip_int64_t
.Fn zip_source_read "zip_source_t *source" "void *data" "zip_uint64_t len"
.Sh DESCRIPTION
The function
.Fn zip_source_read
reads up to
.Ar len
bytes of data from
.Ar source
at the current read offset into the buffer
.Ar data .
.Pp
The zip source
.Ar source
has to be opened for reading by calling
.Xr zip_source_open 3
first.
.Sh RETURN VALUES
Upon successful completion the number of bytes read is returned.
When
.Fn zip_source_read
is called after reaching the end of the file, 0 is returned.
Otherwise, \-1 is returned and the error information in
.Ar source
is set to indicate the error.
.Sh SEE ALSO
.Xr libzip 3 ,
.Xr zip_source 3 ,
.Xr zip_source_seek 3 ,
.Xr zip_source_tell 3 ,
.Xr zip_source_write 3
.Sh HISTORY
.Fn zip_source_read
was added in libzip 1.0.
.Sh AUTHORS
.An -nosplit
.An Dieter Baron Aq Mt dillo@nih.at
and
.An Thomas Klausner Aq Mt tk@giga.or.at
